A Review of Japan' s Medical Care Reimbursement Programs in Primary Care from the Perspective of Social Determinants of Health

There is increasing awareness of the need to incorporate social determinants of health (SDH) into medical practice. However, the extent to which the reimbursement system addresses SDH remains unclear. This narrative policy review aimed to evaluate the Japanese medical reimbursement system to determine whether and to what degree it incorporates assessments and actions related to SDH, with a special focus on primary care settings. We also explored the potential impacts and challenges of these programs in addressing patients' SDH issues. A team consisting of physicians experienced in clinics, hospitals, home care, social epidemiological research, and a community care nurse reviewed the current reimbursement system. They identified eight medical reimbursement programs for evaluation. Two programs directly included SDH elements ("Hospitalization and Discharge Support Fee" and "Guidance in Cooperation with Mental Health Care Fee"). The two programs were introduced in 2022. It was found that SDH assessments are often optional and need more clarity in their items; few programs offer SDH assessments in outpatient and home care settings, and there is no mandate for collaboration with community supporters. We found the Japanese reimbursement system has provisions for some programs involving SDH. However, significant challenges remain that require revision. This study offers insights and recommendations for addressing health disparities related to SDH in the future.